The initiating event in the accident sequence could not be determined. It is most likely that the pilot was departing the accident site and, for unknown reasons, lost control of the aircraft. The damage patterns are consistent with low rotor speed and erratic blade movement that resulted in main rotor strikes of the tail boom. Investigation of the aircraft wreckage and components found no indication of any mechanical malfunction that may have initiated or contributed to the accident sequence. Weather was not considered to be a factor. It is possible that the alternator failure may have distracted the pilot from a low-rotor-speed situation; this could not be determined. It is unlikely that the pilot was wearing his lap-belt/shoulder harness at the time of the accident. It is probable that using the available restraint properly would have lessened his injuries and increased the chance of survival. The following laboratory reports were completed: LP 032/02 - Instrument Analysis LP 033/02 - Exhaust Stack Analysis, Temperature DeterminationAnalysis The initiating event in the accident sequence could not be determined. It is most likely that the pilot was departing the accident site and, for unknown reasons, lost control of the aircraft. The damage patterns are consistent with low rotor speed and erratic blade movement that resulted in main rotor strikes of the tail boom. Investigation of the aircraft wreckage and components found no indication of any mechanical malfunction that may have initiated or contributed to the accident sequence. Weather was not considered to be a factor. It is possible that the alternator failure may have distracted the pilot from a low-rotor-speed situation; this could not be determined. It is unlikely that the pilot was wearing his lap-belt/shoulder harness at the time of the accident. It is probable that using the available restraint properly would have lessened his injuries and increased the chance of survival. The following laboratory reports were completed: LP 032/02 - Instrument Analysis LP 033/02 - Exhaust Stack Analysis, Temperature Determination Low rotor speed and an erratic blade movement resulted in two blade strikes on the tail boom and the break up of the helicopter. The reason for the low rotor speed could not be determined.Findings as to Causes and Contributing Factors Low rotor speed and an erratic blade movement resulted in two blade strikes on the tail boom and the break up of the helicopter. The reason for the low rotor speed could not be determined. The alternator was not producing power for an undetermined time prior to the accident. The pilot was not wearing the available lap-belt/shoulder harness at the time of the accident.Other Findings The alternator was not producing power for an undetermined time prior to the accident. The pilot was not wearing the available lap-belt/shoulder harness at the time of the accident. A Safety Information Letter (No.A020020-1) was sent to Transport Canada on 25July2002. The deficiency identification addresses the lack of any requirement to inspect alternators on Robinson helicopters.Safety Action A Safety Information Letter (No.A020020-1) was sent to Transport Canada on 25July2002. The deficiency identification addresses the lack of any requirement to inspect alternators on Robinson helicopters.